ZHEZKAZGAN,KAZAKHSTAN - MAY 14: Expedition 39 Commander Koichi Wakata of the Japan Aerospace Exploration Agency (JAXA) is carried in a chair to a medical tent just minutes after he and Soyuz Commander Mikhail Tyurin of Roscosmos, and Flight Engineer Rick Mastracchio of NASA, landed in their Soyuz TMA-11M spacecraft on May 14, 2014 near the town of Zhezkazgan, Kazakhstan. Wakata, Tyurin and Mastracchio returned to Earth after more than six months onboard the International Space Station where they served as members of the Expedition 38 and 39 crews. (Photo by Bill Ingalls/NASA via Getty Images) *** BESTPIX ***

Photo: Bill Ingalls/NASA, NASA Via Getty Images

ZHEZKAZGAN,KAZAKHSTAN - MAY 14: Expedition 39 Commander Koichi...

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TOPSHOTS Dust rises near the Russian Soyuz TMA-11M space capsule shortly after its landing, some 150 km (80 miles) south-east of town Dzhezkazgan, Kazakhstan, on May 14, 2014. Three astronauts, including a Russian, Japanese and an American, touched down safely on Earth today aboard a Soyuz capsule, the first such landing since Russia's relationship with the West slumped amid the Ukraine crisis. NASA in April announced that it was cutting space cooperation with Russia over Moscow's Ukraine policies, but that work at the space station would not be affected. In what appeared to be a retaliatory move, Russia's deputy prime minister Dmitry Rogozin said yesterday that Moscow had no plans to keep the station past 2020, even though NASA said in January that the administration of Barack Obama has extended the station's lifespan to 2024. AFP PHOTO / POOL/ DMITRY LOVETSKYDMITRY LOVETSKY/AFP/Getty Images

Photo: Dmitry Lovetsky, AFP/Getty Images

TOPSHOTS Dust rises near the Russian Soyuz TMA-11M space capsule...

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U.S. astronaut Rick Mastracchio is helped shortly after the Russian Soyuz TMA-11M space capsule landed, some 150 kilometers (93 miles) southeast of town Dzhezkazgan, Kazakhstan, Wednesday, May 14, 2014. The Soyuz space capsule with Mastracchio, Japanese astronaut Koichi Wakata and Russian cosmonaut Mikhail Tyurin, returning from a half-year mission to the International Space Station, landed safely Wednesday on the steppes of Kazakhstan. (AP Photo/Dmitry Lovetsky, Pool)

Photo: Dmitry Lovetsky, Associated Press

U.S. astronaut Rick Mastracchio is helped shortly after the Russian...

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Russian traditional wooden dolls Matryoshka depicting, from left, Japanese astronaut Koichi Wakata, Russian cosmonaut Mikhail Tyurin and U.S. astronaut Rick Mastracchio, stand on a table during a welcome ceremony at the airport in Karaganda, Kazakhstan, Wednesday, May 14, 2014. Russian Soyuz TMA-11M space capsule carrying the three, returning from a half-year mission to the International Space Station landed safely Wednesday on the steppes of Kazakhstan. (AP Photo/Dmitry Lovetsky, Pool)

They were pulled from the hatch at the top of the capsule and maneuvered down a slide into lounge chairs set up nearby and given brief medical assessments as they readjusted to gravity after six months of weightlessness. All appeared to be in good condition and Tyurin was heard joking that he'd like some red wine.

Russians Alexander Skvortsov and Oleg Artemyev and American Steve Swanson remain aboard the station. Three more astronauts are to launch for the station on May 28.

The landing came less than a day after Russian Deputy Prime Minister Dmitry Rogozin said Russia wouldn't continue cooperating with the U.S. on the 15-nation ISS past 2020. The United States has relied on Russian Soyuz capsules to fly to and from the space station since NASA retired its space shuttle fleet. NASA hopes that private companies such as Space X founded by Tesla Motors CEO Elon Musk will be able to develop rockets and capsules to fly astronauts to the space station within a few years.